The present invention relates to an apparatus and a process for the manufacture of a two-part foam product having a cellular body portion of one material and a thin integral ski n coating applied and fused to the outer surface of the body portion.
Extruded polyethylene foam products are commonly available and in many cases have a circular cross section. It is possible to manufacture other cross sections, however, these are more difficult, particularly when the size of the extruded product is large. Foam products produced by extrusion have an extrusion skin which is formed during cooling of the product and is of the same material as the body portion.
The density of extruded foam products is easily controlled and the nature of the product normally requires a certain density for the particular application or desired durability. For example, if the foam product is being used as a bumper for boats, the density would be relatively high.
There are some applications for extruded foam products where it would be desirable to provide a skin coating on the surface of the extruded product to impart to the exterior of the product, characteristics different from the material characteristics of the foam body. In some cases, it is desirable to impart a protective coating to form a sheath about the extruded foam product. Extruded sheath foam products are used as a protective wrap about structural members such as playground equipment, exercise equipment or structural members such as basketball poles or protective pads about exercise equipment. In such cases it is desirable to alter the surface characteristics of the extruded foam product by the application of an integral skin of a different material to provide different properties to the product or to make the product suitable for a particular application.